1) Drain oysters, strain the juice and save it. Pick over oysters carefully with your fingers to get rid of any shell. Leave oysters whole if small. Halve, if large. Set aside.
2) Cook slowly, stirring, the Mazola, celery, bell pepper and white onion. In about 7 minutes the onion should be transparent, but not brown. Measure strained juice, fill up to 2-1/2 cups with hot water and add 4 chicken bouillon cubes. Add to cooked seasoning with the bay leaf, thyme, Tobasco and Worcestershire sauce. Boil 5 minutes. Remove bay leaf. Add raw rice, green onions and parsley. Pour in buttered casserole, distribute oysters evenly, and cover tightly. Bake at 350 degrees for 45 minutes. Uncover, stir once, cover again, and bake 15 more minutes.